Platen-adjusting mechanism



sept. 1s, 192s. 1,684,429-

J. H. BARR PLATEN ADJUSTING MECHNI SM Filed Oct. '7, 1925 Patented Sept. '18, 1928.

UNITED STATES PATENT OFFICE.

JOHN rr. BARR, or ITHACA, NEW YORK, AssIGNOB. To minar/Ionen CORPORATION, A

' CORPORATION OF NEW YORK. l

IPLATEN-ADJUSTING MECHANISM.

Application filed October 7, 1925. Serial No. 60,974.

c This invention relates to platen adjusting mechanism for typewriters, adding machines and similar devices. In such devices, the platen is usually line-spaced by a ratchet wheel that is driven or manipulated by suitable meehani sm, theA platen and ratchet wheel being coupled in a suitable manner enabling their disconnection from one another and thereby permitting separate rotation of the platen. It is frequently desirable, particularly in typewriting machines, to adjust the platen independently of the driving ratchet wheel, as when positioning the paper or sheet being printed uponso that the printing will occur in any particular part of the sheet or paper, and after such adjustment to effect a recoupling of the ratchet wheel to the platen so that the ratchet wheel will properly space or rotate the platen angularly through the usual spacing increments from the newly adjusted position. Heretofore, such adjustment has been commonly controlled by special added appliances which increased the number of parts and thereby increased the cost of manu facture, and with whose use an operator must become familiar. With prior devices it has often been necessary to utilize both hands when making such an adjustment, one to release the platen and the other to turn it after release. There was .no provision for taking up wear, and when a coupling or uncoupling of the platen and ratchet wheel was controlled by an element shiftable ina direction lengthwise of the platen, and the ratchet wheel was disposed at the left hand end of the platen, it has been usually necessary to hold the carriage while the controlling element was shifted to release the platen.

An object'of this invention is to provide an improved platen adjusting mechanism, with which an operator may, with one hand, with` out holding the carriage, and by engaging a single part, release the platen from its operating mechanism and adjust it to any desired angular extent and then recouple it to the ratchet wheel in such adjusted position; with which no additional controlling or operating handles or parts will be required; which will have a satisfactory, dependable, and adjustable driving connection between the ratchet wheel or operating mechanism andthe platen; with which the extent of the friction of coupling m ay be varied to suit individual desires or to compensate for wear which will be come pact, convenient, dependable, easily manipulated, simple, and relatively inexpensive.

Various other objects and advantages will justing mechanism constructed in accordancel with this invention; and

FigQQ is an end elevation of the same.

In the illustrated embodiment of the invention a platen shaft 1 is rotatably and slidably mounted in bearings 2 and 3 supported in fra-me brackets or members 4 of the carriage, the bearings being preferably removably carried by said brackets 4 in order to enable the removal of the platen when desired. Any suitable means (not shown) for locking the bearings to the frame 4 may be employed. A platen cylinder 5 surrounds the platenfshaft 1 and may be provided with end'walls 6 and 7 which are removably attached thereto in any suitable manner, such as by screws 8 which pass through the end walls and into engagement with the ends of the cylinder 5. rlhe cylinder 5 .carries the usual or any suitable platen or roller printing surface.

The end wall 6 of the cylinder is provided with an inwardly extending hub portion 10 whichy slides along and upon the shaft 1. The hub portion 10 is provided with a longitudinally extending slot 11 and the shaft 1 is provided with a transversely extending pin '12 which engages in said slot 11, so as to provide a keyed connection between the platen. cylinder and shaft and cause their concomitant rotation while permitting independent endwise movement of the platen shaft. A single slot 11 may be employed with the pin 12 projecting only from one side of Vthe shaft, but preferably and for various reasons, such as because of manufacturing advantages, two slots 11 are provided upondiametrically opposite sides of the hub portion 'and the pin 12 projects diametrically from opposite sides of the shaft and into both slots 11. The outer face of the end wall 6 may be provided.k with a recess 18 for receiving a flange 141 provided upon a portion of the bearing 2 and which projects along the shaft 1 from the portion of the carriage frame 4 to which it is attached.

A plate 15 is fitted against the outer face of the end Wall 6 of the cylinder and is secured thereon ,by screws 8 which secure the end Wall to the cylinder'. The plate 15 fits over the bearing 2 and against the flange '14 so as to prevent its removalfrom the recess 13. The flange 14 of the bearing 2 is thus coupled to the end Wall of the platen cylinder in such a manner as to prevent endwise movement of the platen cylinder While permitting free rotation of the cylinder and its end Wall 6. The plate 15 may be formed` either in tivo sections to `enable it to be fitted around the bearing 2, or it may have a slot from one edge thereof of a. Width corresponding to the diam eter of the bearing 2 so that it may be slid over the saine.

4The end 'Wall 7 of the Cylinder is prof vided With an aperture 16 surrounding and larger than Athe shaft 1, in which aperture a sleeve 17 slidable upon the shaft 1 is also slidable endwise to various extents therethrough. Thesleeve is provided at its inner end 'with an outwardly peripheral lia'ngev18, and at. its

Vouter projecting end 4is screW threaded as at 19. A ratchet Wheel 20 is threaded upon the outer end ofthe sleeve 17 and locked in various adjusted positionsthereon by anut 21, also threaded upon the threaded end of the sleeve 17. The outer end of the sleeve is preferably provided with one or more notches 22 for receiving a suitable tool, whereby the sleeve maybe held against rotation While the ratchet Wheel and nut are being threaded therealong to various extents.

The ratchet Wheel, upon its face abutting the end Wall 7 is provided with. an annular groove 23 somewhat Vsshaped in cross section, and the corresponding abuttingface of the end Wall 7 is provided With an annular rib 24 also somewhat V-shaped in cross section and. of such a size as to fit Within the groove 23. The rib 24 and groove 23 "thus, in eiieohserve as a frictional clutch between the ratchet Wheel and the cylinder, the V,- shape increasing the frictional surface and resistance between them and also compensat-` ingfor wear during use. Furthermore, by the use of the V-sh ape for the groove and rib, there is a somewhat Wedge-like action between the walls of the groove and the rib when Vthe ratchet Wheel fis moveden'dvvise, thus providing a more effective `frictional coupling between the ratchet Wheel and cylinder.

The end `Wall 7, `upon itsinner face is provided Withbearing ears 25 upon which bell crank clutch levers 26 are pivoted'by pins 27. Each lever 26 has a shorter arm 28 which extends transversely of the shaft 1 and'engages behind the flanged head 18 of the sleeve 17. The other and longer arms 'of the levers 29 extend along the shaft 1 Within the cylinder Vof an abutment element 31 which is slidable upon the shaft 1 Within the cylinder. A helical vcompression spring 32 is provided upon the shaft 1 Within the cylinder andl bears at one end against the flanged head 18 of the sleeve 17 and at its other end against the cam element 31, so as to normally urge the cam element in a direction to separate, by a Wedg ing action of the tapered cam surface, the long clutch arms 29 of the clutch levers;

VA pin 33 carried by the shaft 1 vv'ithin the cylinder may be provided to force the cam element xendwise against the action of its 'spring and release the clutch levers When the shaft 1 is shifted endvvise, that is to the left in Fig. 1. The shaft 1, at both ends, is providedwith-an operating button 34 by which it may be rotated and also shifted endvvise from the full line position shown in Fig. 1, where theratchet Wheel and platen cylinder are coupled, to the dot and dash position also shown in the same figure and in which the ratchet vvheel and cylinder are uncoupled. The spring 32 will always hold the abut` ment element or Wedge 31 against the pin 33 and, therefore, the wedge or abutment element 31 could just as well `be formed as an integral part of the platen shaft 1 `or be pinned thereto so far as its operation is concerned- However, the assembly of the mechanism ofthe platen is simpler when the abutment or Wedge element is freely slidable upon the platen shaft and abutting against the pin 33, as illustrated, and for that reason this illustr'ated construction is somewhat preferable.

Considering thev operation of this mechanism, the normal position of the various parts is shown in the drawings in full lines, the shaft 1 being urged to its furthest position to the right by the spring 32 acting thereon through the cam element 31 and the pin 33. Inthis condition of the parts, the cam elenient 31 has wedged the clutch lever arms 29 apart. so that the shorter arms 28 of the levers 26 will pull the sleeve 17 inwardly. The sleeve in moving inwardly Vwill carry the ratchet wheel into frictionally 'coupled engagement with the end Walls 7 of the cylinder and, therefore` Whenever the ratchet wheel is operated, its motion will be transmitted to the platen cylinder and the printing surface 9 thereof.

While the spring 32 acts at one end to shift `the sleeve 17 in one direction and at its other end vthrough the cam element and levers 26 las the platen element from the ratchet wheel he will merely shift the platen button 84 to the left into the dot and dash lines shown on the drawing, during which movement the shaft l will be shifted endwise. The pinf of the shaft` l during such movement will force the cam element 31 to the left in Fig. l, against the action of the spring 32 and thus release the sleeve 17. The sleeve 17 will then move outwardly sufficiently to release the pressure between the abutting faces of the ratchet wheel and end wall 7 and as a result, there will be no eriving friction between them. Rotation of the button 3ft while in its new endwise position will thus rotate the platen element without moving the ratchet wheel.

It will be observed that the platen shaft is always rotatably coupled to the platen cylinder through the pin 12 which has Va keyed relation with the end wall 6 of the Y cylinder. Upon a release of the platen knob it will be forced endwise to its full line position by the spring 32 which shifts the shaft l endwise through the cam 3l and pin rihe cam 3l in moving with the shaft i4 to the full line position will force the arms 29 of the clutch levers apart, dravv the sleeve 17 inwardly, and force the ratchet wheel into frictional engagement with the end wall 7 of the platen element, thus effecting a recoupling of the ratchet Wheel and platen element. Then when the ratchet Wheel is given increments of movement, these 'increments will be imparted to the platen printing` surface 9 starting from the newly adjusted position.

The ratchet. wheel 2O is preferably mounted at the left hand end of the platen, and

since movement of the carriage to the left, as usual, is controlled by the escapement, the latter will hold the carriage stationary while the platen shaft is given endwise movements in effecting an uncoupling of the platen and ratchet wheel, and thus it is merely necessary for a typist to employ but one hand in releasing and turning the platen in making an adj ustment. The carriage will not be unintentionally back spaced, asis often the case where an uncoupling of the platen from the ratchet wheel is accomplished by an element that moves in a back spacing direction on the carriage. v

l)y providing for the adjustment of the ratchet wheel, great accuracy in the manufacture of the various parts is unnecessary, and thus the production cost is lowered.` Since the arms 28 are short, relatively to the arms 29, a slight variation in the edges of the arms 28 which engage the iiange 18 will be greatly amplified at the free ends of the long arms 29. vWith this invention, the parts may be produced by the least expensive operations, and after assembly a simple adjustment of the ratchet wheel 2O and the nut 2l upon the sleeve ii' will compensate for any variations in the other parts of the coupling mechanism.

It will be observed that the disconnection of the platen element from the ratchet wheel, and its rotation or adjustment to new positions, is accomplished entirely by the single convenient manner. The coupling obtained in this manner between the vratchet wheel and platen is very efficient, dependable, durable and the entire construction exceptionally sim# ple and relatively inexpensive.

It will be obvious that various changes in the details, which have been herein described and illustrated for the purpose of Xplaining the nature of the invention, may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims, Y

l. In platen adjusting mechanism, a platen shaft, spaced apart bearings supporting saidA shaft for endwise and rotary motion, a platen core disposed on said shaft between said bearings and coupled to said shaft in such a manner that the platen will always be rotated upon rotation of the shaft and the'shaft may be shifted endwise without interruption of the driving connection between it and the core, a ratchet wheel, a sleeve slidable and rotatable on said shaft andy mounting said ratchet wheel, andr means controlled by endwise movement of the shaft for drawing said sleeve into said core to frictionally couple the ratchet wheel and core for concomitant rotation, and operable to cause a release of said sleeve when disconnection of the ratchet wheel and platen is desired.

2. ln a 'platen adjusting mechanism, a platen shaft, meansfor mounting said'shaft for endwise and rotary motion, a platen core through. which the shaft passes and coupled to said shaft for concomitant rotationvtherewith while permitting independent endwise movements of said shaft, a sleeve slidable and rotatable on said shaft and extending through an end of said core, a ratchet wheel mounted upon the outer end of said sleeve so as to be movable with said sleeve against and away from an end wall of said platen core, clutch levers act-ing` between the sleeve and core lfor drawing said sleeve into the core to frictionally couple the ratchet wheel and core, and means controlled by the endwise movements of the shaft for operating said clutch levers.

3. wfn a platen adjusting mechanism, a platen shaft,.means for mounting said shaft anend otsaid core, a ratchet wheel mounted uponthe outwardly projecting poi'tion ot said sleeve so as to be movable with said sleeve platen core, clutch levers acting between the sleeve and core for drawingl saidl sleeve into the core to frictionally couple the` ratchet wheel and core, a cam movable in a direction along the axis ot the shaft and having a cam surface controlling said clutch levers, a spring acting upon said cam member to urge it in a direction to cause a coupling operation of said clutch` arms, and-means operable by the shaft during an endwise movement for operating the cam element against the action of said spring in a direction to release the-sleeve and permit o't separation ot theratchet wheel and platen core.

4. In a platen adjusting mechanism, a platen shaft, means for mounting said shaft for endwise and rotary motion, a platen element coupled to said shaft for rotation therewith, a ratchet wheel, clutch means acting `between the platen element and ratchet wheel for causing relative movement` of said platen element and ratchet wheel into and out of i driving engagement with one another, said clutch means including relatively movable parts, one of said parts having a section adjustable thereon independently of the said relative movement to compensate for wear, means normally urging `said clutch means in aI manner to cause coupling of the ratchet wheel and platen element, and. means operable by the shat't during an endwise'movement independentiy of the platen for causing operation of said clutch means to uncouple the ratchet wheel and platen element and permit of their independent relative rotation.

5. In a platen adjusting mechanism, a platen element anda ratchet wheel element relatively movable into and out of coupled engagement with one another, one olf-said ele ments having two sections, means acting between one of said sections and the other ele? ment toV produce relative movement and etect a coupling between the other of said sections and saidother element` said one of said sections being adjustable on the iirst section independently of such relative movement t0 facilitate Yadjustment of said element rela'- tively` to one another, and means for causing relative movement of said elements to couple vor release them.

6. In a platen adjusting mechanism, a platen shaft, means ior mounting said' shaft for endwise and rotary motion, a hollow platen element coupled to said shaft for rotation therewith and permitting independent against and away from the end wall oiE said endwise movement of said Shaft, a ratchet wheel, a supportingV element for said ratchet wheel passing into the interiorof saidA platen element, levers carried by one'of said elements and havingarmsactingupon the other of said'l elements to draw them, into coupled engage- `ment with one another, and also having operating arms extending along the platen shalt, a. wedge carried byv said shaft and acting upon said operating arms of the levers to ettecta coupling et the ratchet wheel and platen element, a spring acting to shift said wedge in a direction to cause aV couplingof the ratchet wheel and platen element, said wedge being` movable by an endwise movement ofthe shaf against the action of the spring in a direction 'to release the operating arms and thereby effeet a disconnection of the driving relation' between the ratchet wheel and platen element.

7. In aplaten adjustingy mechanism, fr platen shaft, means mounting saidshaft for endwise and rotary motion, aplaten cylinder' having end walls through which the shaft passes,one of said end walls having a connection to Vsaid shaft, Such that the shaft may be movable endwise independently of the rplaten and while remainingirotatably coupled'there-r to, means for preventing endwise movement ot said platen with the shaft, a sleeve `surrounding the shaft and passing through an end wall of the platen cylinder, a` ratchet wheel carried by said sleeve'exteri'orly of the cylinder and movable with thesleeve toward? and from the end walli of saidY cylinder through which the sleeve passes, levers carried by said cylinder and having armsengaging with said sleeve to pull the ratchetwheel j against theend wall ofthe cylinder, said levers having relatively longer operating arms extending along the shaft within the cylinder, a` wedge carried by the shaft and having a tapered cam surface for. separating said lever arms whichextend along the sh aft and thereby cause an inward movement of the' sleeve,a spring surrounding the shaft and acting between the sleeve and the wedgeA l passes, one of said end Walls havinga connection to said shaft, such thatthe shaft may be movable endwise independentlyof the platen and while remaining rotatably coupled thereto,imeans for preventing endwise movement of said platen with the shaft, a

sleeve surrounding the `shaft and passingV through an end wall of the platen cylinder, a ratchet wheel mounted on said sleeve and adjustable lengthwise of the same, levers carried by said cylinder and having arms engag ing with said sleeve to pull the ratchet wheel against the end wall of the cylinder, said levers having relatively longer operating arms extending along the shaft Withinthe cylinder, a wedge carried by the shaft and hav! ing a tapered cam surface for separating said lever arms which extend along the shaft-and thereby `anse an inward movement of the sleeve, a spring surrounding the shaft and acting between the sleeve and the wedge for normally urging the wedge in a direction to effect a coupling of the ratchet wheel and cyl inder, and an abutment carried by the shaft and engageable with the wedge during endwise movement of the shaft in one direction to force the wedge inv a direction to release the operating arms of said levers and thereby effect a disconnection between the ratchet wheel and cylinder.

9. In a platen adjusting mechanism, a plat# en shaft, means for mounting said shaft for endwise and rotary motion, a hollow platen element coupled to said shaft for rotation therewith and permitting independent endwise movement of said shaft, a sleeve element slidable on said shaft through the end of said platen element, a ratchet wheel carried by the outer end of said sleeve element so asto be movable with the sleeve element against the end of the platen element, clutch levers carried by one of said elements and acting upon the other element to produce relative movement between said elements and thereby draw the ratchet wheel and the platen element into driving' relation with one another, said levers having operating arms extending along the shaft, means for moving said operating arms in directions to couple said ratchet wheel with the platen element or for releasing them, and means including said shaft andaspring for normally urging said means in a direction to effect a coupling of said ratchet wheel and platen element, and operable to effect a disconnection of said ratchet wheel and platen element.

l0. In a platen adjusting mechanism, a platen shaft, means for mounting said shaft for endwise and rotary motion, a hollow platen element coupled to said shaft for rotation therewith and permitting independent endwise movement of said shaft, an. element movable through the end of said platen element, a ratchet wheel carried by the outer portion of said movable element so as to be movable therewith against the end of the platenelement, clutch levers carried by one of said elements and acting upon the other element to produce relative movement between them and thereby draw the ratchet wheel into driving relation with the platen element, said levers having operating arms extending along the shaft, means carried by the shaft for moving said operating arms in directions to either couple said ratchet Wheel with the platen element or release them, and a spring normally urging said means in a direction to effect acoupling of said ratchet wheel and platen element, said means and shaft cooperating together to effect a disconnection of said ratchet wheel and platen element upon an endwise movement of the shafi'i, said shaft supporting means 4engaging with the platen clement to prevent its axial'n'iovement with the shaft.

ll. ln a platen adjusting mechanism, a platen shaft, a carriage frame, bearings provided onj said frame and supporting said shaft for endwise and rotary motion, a platen element coupled with the shaft for rotation therewith and permitting independent endwise movement of saidshaft, one of said bearing elements having a' peripheral iiange, said platen element having means cooperating with said flange to prevent endwise movement of said platen element while permitting free rotary movement thereof, a ratchet wheel, means for coupling said ratchet wheel and platen element for rotation together, and means carried by said shaft operating by endwise movements of the shaft for effecting a disconnection of said ratchet wheel and platen element.

12,111 a platen adjusting mechanism, a platen shaft, means for mounting said shaft for endwise and rotary moti-on, a platen cylinder having end walls surrounding said shaft, one of said end walls being coupled to said shaft for rotation therewith and permittingy independent endwise movement of said shaft, a sleeve slidable on said shaft and passing through an end wall of said cylinder, a ratchet wheel mounted on the outer end of said sleeve, means within the cylinder for drawing said sleeve into the cylinder and carrying the ratchet wheel into frictional driving relation with an endwall of the cylinder, said lastnamed end wall and saidl ratchet wheel having upon their abutting faces cooperating V-shaped grooves and ribs for providing a maximum frictional engageA ment between them and for compensating for wear.

13. In a platen adjusting mechanism, a platen shaft, means for mounting said shaft for endwise and rotary motion, a platen cyl! inder having end walls surrounding said shaft, one of said end walls being coupled to said shaft for rotation therewith and permitting independent endwise movement of said shaft, a sleeve slidable on said shaft and passing through an end wall of said cylinder, a`

ratchet wheel mounted on the outer end of said sleeve, means within the cylinder and controlled by said shaft for drawing said sleeve in a direct-ion to carry said ratchetwheel into frictional driving relation with an end wall of the cylinder, a nut carried by said `sha-ft, a'A sleeve slidable on said shaft and pass'- ing through an end Wall of said cylinder, a ratchet Wheel-mounted onthe .other end of said-sleeve, means controlled by said:` shaft during.; its endwise movements for ,shifting said; sleeve tocarry theV ratchet wheel into and outiof frietioiial-drivingrelationf vvithan end'wallofsaid cylinder,anda'nutcarried by the-sleeve orloeking'saidfratchet-wheel tothe sleeve in-A dilfererrt ealjustedy posit-ionsA along thetsleeve whereby the ratchetwheel may be adjustedealong. the sleeve tocompensate forv Wearandto-'obta'in al desired initial frictional engagement With the-platen'.

A15: I'n; a" platen adjusting mechanism, a'

platen element, a ratchet Wheel, asleeve on which said; ratchet" wheel is mounted and along! which" itis adjustable; said sleevev andV platen element being relatively movableA to` cause a 4frictional couplingfor nconplingi` of;

the `platenVV element andA ratchet| Wheel, and' Y means for .shitting said sleeve to effect ori' bre'a'k a" driving connection between" said" ratchetwlieel and platen elementrV 16. In" a' platen adjusting mechanisn'r,M atA platen"element,` a ratchet Wheel, a" sleeve on"v which said ratchet' wheel is' mounted and` along which it is adj1ustable,f.said sleeve and platen element being relatively movable' to" cause a' frietionalleonpl'ing or unccniplingv or the' platen element and-` ratchet wheel, and

meansfor shifting-said sleeve to'ettfector break af driving connection betweenV said ratchet wlnee1"`,.a1jdA platen element, said" means being controllable from the end 'of the platen element opposite fromthe ratchet Wheel.

1'7".` In platen adjusting mechanism, a

platen shaft, means supporting said shaft `for endwise and" rotaryimotion, a platen core coupled to said shaft in such a manner that the platen WillalWays be rotated upon rotation of the shaft and the shaft may be shifted endwlse Without interruption of the driving.

connection between it and the core, a ratchetl Wheel, aslecvej sllidable and rotatable on said shaft, said ratchet Wheel being mounted on said sleeve `for adjustment axially thereof, and:

mea-ns, controlled by endvvise movement of said shaft for drawing said sleeve into said` core to frietionally cokuplethe ratchet Wheel and core: for concomitant rotation' and' .operable to cafuse a `releasevof said sleeve when disconnection ofth'eratchetwheel and platen isdesired.Y

18. In a platen adjusting mechanism, a

platen shaft, means for mounting saidJ shaft forehdvvise and rotary motion, a hollow platen element coupled `to said shaftfor rotation therewith and permitting` independent endwisem'ovement ofsaid shaft, a sleeve elementslidable on saidshaft through the end of,y

saiduplaten element, a ratchet wheel carried 7a bythe outer endotfsaid sleeve element so as to be movable with ,the sleeve element a ainst` the' endof` the platen element,1 clutchV evers carriedby one of said elements and actingupon the' other element to produce relative movement betweensaid elements and therebyV drawthe ratchet- Whcel" andthe platenA elenrerrtW` into driving relationwith one another, saidlelvers having I operating arms extending along theshaft-,fandmeans controlled by end- Wisemovement oft said; shaft for operating said: armsfto-fictionally couple or uncouple the ratchetjwhe'el and platen element by causing-fendwisel movement of said sleeve element.

In .Witness whereohI hereunto subscribe mysighaturre.- Y v .i t

p `JOHN H. BALRR.` 

